This piece mounts on top of the valve; mounted to this is the handwheel and gearbox assembly (mfgr calls it base assembly), then actuator mounted on top of these two items
NSN 5905-01-422-0127
NSN 6220-01-505-6072
NSN 5835-01-561-2959
NSN 5895-01-401-5388
NSN 6320-00-456-2092
NSN 5915-00-875-2101
NSN 5905-01-382-0013
NSN 6645-01-497-6543
NSN 6620-01-541-5480
NSN 5925-01-318-5930
NSN 5945-01-314-7245
NSN 5975-00-169-1401